O.S. Speed R2106 .21 9-Port On-Road Engine Combo Set w/ TR03 EFRA2196 & MR04

Features:

• Cylinder Liner: This engine boasts a 9-port piston liner to improve torque in low-middle power range. It produces enough power as designed even for high traction tracks.
• Outer Head: Distance between the cooling fins is enhanced for better air flow and better balance. The heat sink head is anodized in two colors: black and red.
• Inner Head: A silicon O-ring fit to the inner head prevents dust from coming into the engine.
• Crankshaft: The redesigned crankshaft counter weight enables smooth power transition from low to top.
• Carburetor: The carburetor is 21M2(B), which has been proved to be consistent and reliable for generations (R2104, R2105)
• Combo Set: This combo includes TR03 EFRA2196 & MR04, which works to improve air flow - the MR04 complete set.